Pre-filled medicament containers are used in a vast variety of medicament delivery devices and in particular for self-administration of medicament. Many of the medicament containers used are pre-filled containers that are placed in the medicament delivery devices before delivery. In order to make the medicament delivery device ready for delivery of medicament a medicament delivery member, such as an injection needle, is attached to a proximal end of the container.
In order to standardize the connection between the medicament container tip and the delivery member, e.g. an injection needle, the luer taper system has been developed. It comprises two variants, the luer slip and the luer lock systems. The luer taper system has been widely accepted and used due to its relative simplicity, which also facilitates handling and attachment of the delivery member to the medicament container.
However, a drawback with most medicament delivery systems has been that they can be opened and closed unnoticed, a shortcoming which favours tampering and even product counterfeits. There is thus a demand for devices that are easy to use but that still provide tamperproof connection of a delivery member with a medicament container.
In view of the above mentioned demand, a tamper evident luer lock closure unit or TELC unit, has been developed. It comprises an attachment part having a luer lock or luer taper fitting. To the attachment part a closure cap is threadedly connected and thus the closure cap is twisted off when removed—not lifted off.
The controlled twisting motion has the advantage that accidental spillage of the medication is largely avoided, which otherwise often occurs with other types of delivery member shields that are pulled off, because of the jerky opening action.
The tamper evident function comprises lugs on the closure cap that are released by the twisting motion, which lugs then immediately drop away slightly. It is practically impossible to close the syringe again completely, whereby it is evident that the closure cap has been removed.
Even though the TELC unit has a number of advantages, there are some issues that need to be addressed in conjunction with medicament delivery devices, and in particular devices having a certain degree of functionality such as for example auto-injection. Because the TELC unit has a rather large and in particular wide cap, with a diameter that is often larger than the diameter of the medicament container, it may be difficult to fit it into a container holder or housing, in particular if the medicament container is arranged with a circumferentially outwardly directed flange, often made integral with the medicament container. It is then impossible to position the medicament container in a tubular holder or housing unless it is inserted from the distal end of the holder or housing. Even so, the support in the proximal end of the medicament container may not be adequate since there is an annular gap between the outer surface of the proximal area of the medicament container and the holder or housing.
One solution to solve this problem is to attach the TELC unit to the proximal end of the medicament container after the medicament container has been placed in the holder or housing in order to have the medicament container with the TELC unit in the operative position within the medicament delivery device. This is not optimal since it would demand a more expensive process of assembling a medicament container with a TELC unit in a holder or a housing of a medicament delivery device. It would demand that the medicament container is placed in the holder or in the housing directly after filling the container with medicament, that the TELC unit is attached to the container and then that the assembled container with the TELC unit is sterilized. Further, if the container with the TELC unit is to be used in a reusable medicament delivery device, the container with the TELC unit must be provided to a patient or to a user. Then the container with the TELC unit must be delivered to the patient or to the user as a unit which is sterilized. The container and the TELC unit cannot be delivered in two parts to be assembled by the user.